package com.example.myapplication.library;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.AnimatorSet;
import android.animation.ObjectAnimator;
import android.content.Context;
import android.content.res.Configuration;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import android.widget.LinearLayout;

import com.example.myapplication.R;

/**
 * Description:
 * <p>
 * Created by rowandjj(chuyi)<br/>
 * Date: 16/1/6<br/>
 * Time: 下午4:50<br/>
 */
@SuppressWarnings("unused")
public class VerticalBannerView extends LinearLayout implements BaseBannerAdapter.OnDataChangedListener {

    private float mBannerHeight = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,40,getResources().getDisplayMetrics());
    private int mGap = 4000;
    private int mAnimDuration = 1000;

    private BaseBannerAdapter mAdapter;

    private View mFirstView;
    private View mSecondView;

    private int mPosition;

    private boolean isStarted;
    private Paint mDebugPaint;

    public VerticalBannerView(Context context) {
        this(context,null);
    }

    public VerticalBannerView(Context context, AttributeSet attrs) {
        this(context, attrs,0);
    }

    public VerticalBannerView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context,attrs,defStyleAttr);
    }


    /**
     * bannerHeight banner的高度
     * animDuration 每次切换动画时间
     * gap banner切换时间
     *
     * */
    private void init(Context context, AttributeSet attrs, int defStyleAttr) {
        setOrientation(VERTICAL);
        mDebugPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.VerticalBannerView);
        mGap = array.getInteger(R.styleable.VerticalBannerView_gap,mGap);
        mAnimDuration = array.getInteger(R.styleable.VerticalBannerView_animDuration,mAnimDuration);

        if(mGap <= mAnimDuration){
            mGap = 4000;
            mAnimDuration = 1000;
        }

        array.recycle();
    }

    /**
     * 设置banner的数据
     * */
    public void setAdapter(BaseBannerAdapter adapter){
        if(adapter == null){
            throw new RuntimeException("adapter must not be null");
        }
        if(mAdapter != null){
            throw new RuntimeException("you have already set an Adapter");
        }
        this.mAdapter = adapter;
        mAdapter.setOnDataChangedListener(this);
        setupAdapter();
    }

    public void start(){
        if(mAdapter == null){
            throw new RuntimeException("you must call setAdapter() before start");
        }

        if(!isStarted && mAdapter.getCount() > 1){
            isStarted = true;
            postDelayed(mRunnable,mGap);
        }
    }

    public void stop(){
        removeCallbacks(mRunnable);
        isStarted = false;
    }


    private void setupAdapter() {
        removeAllViews();

        if(mAdapter.getCount() == 1){
            mFirstView = mAdapter.getView(this);
            mAdapter.setItem(mFirstView,mAdapter.getItem(0));
            addView(mFirstView);
        }else{
            mFirstView = mAdapter.getView(this);
            mSecondView = mAdapter.getView(this);
            mAdapter.setItem(mFirstView,mAdapter.getItem(0));
            mAdapter.setItem(mSecondView,mAdapter.getItem(1));
            addView(mFirstView);
            addView(mSecondView);

            mPosition = 1;
            isStarted = false;
        }
        setBackgroundDrawable(mFirstView.getBackground());
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        if(LayoutParams.WRAP_CONTENT == getLayoutParams().height){
            getLayoutParams().height = (int) mBannerHeight;
        }else{
            mBannerHeight = getHeight();
        }
        if(isInEditMode()){
            setBackgroundColor(Color.GRAY);
            return;
        }
        if(mFirstView != null){
            mFirstView.getLayoutParams().height = (int) mBannerHeight;
        }
        if(mSecondView != null){
            mSecondView.getLayoutParams().height = (int) mBannerHeight;
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if(isInEditMode()){
            mDebugPaint.setColor(Color.WHITE);
            mDebugPaint.setTextSize(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,16,getResources().getDisplayMetrics()));
            mDebugPaint.setStyle(Paint.Style.STROKE);
            canvas.drawText("banner is here",20,getHeight()*2/3,mDebugPaint);
        }
    }

    @Override
    public void onChanged() {
        setupAdapter();
    }


    private void performSwitch(){
        ObjectAnimator animator1 = ObjectAnimator.ofFloat(mFirstView,"translationY",mFirstView.getTranslationY()-mBannerHeight);
        ObjectAnimator animator2 = ObjectAnimator.ofFloat(mSecondView,"translationY",mSecondView.getTranslationY()-mBannerHeight);
        AnimatorSet set = new AnimatorSet();
        set.playTogether(animator1,animator2);
        set.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                mFirstView.setTranslationY(0);
                mSecondView.setTranslationY(0);
                View removedView = getChildAt(0);
                mPosition++;
                mAdapter.setItem(removedView,mAdapter.getItem(mPosition%mAdapter.getCount()));
                removeView(removedView);
                addView(removedView,1);
            }

        });
        set.setDuration(mAnimDuration);
        set.start();
    }
    private AnimRunnable mRunnable = new AnimRunnable();
    private class AnimRunnable implements Runnable{

        @Override
        public void run() {
            performSwitch();
            postDelayed(this,mGap);
        }
    }


    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        stop();
    }

    @Override
    protected void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
    }
}
















